1. Field of the Invention
The present invention generally relates to a suspension device of an in-wheel drive unit. More specifically, the present invention relates to a suspension device of an in-wheel drive unit having a motor as a power source disposed on an inner peripheral side of a wheel rim.
2. Background Information
An in-wheel drive unit suspension device has an advantage that a larger passenger compartment space positioned above a suspension device can be secured because the drive unit is disposed at a lower portion (wheel side) of the suspension device rather than at an upper portion of the suspension device (vehicle body member side). On the other hand, in a structure of the in-wheel drive unit suspension device in which the drive unit is suspended at the lower portion of the suspension device, there is a disadvantage that the driving reaction force of the drive unit imparts a vertically directed force that is inputted to the upper portion of the suspension device. Accordingly, Japanese Laid-Open Patent Publication No. 10-304645 discloses an example of a conventional in-wheel drive unit suspension device in which the in-wheel drive unit and the vehicle body are coupled together by an arm that extends in the vehicle widthwise direction to prevent the suspension device from imparting force in the vertical direction to the vehicle body as a result of the driving reaction force from the in-wheel drive unit.
Moreover, Japanese Laid-Open Patent Publication No. 8-276761 discloses another example of a conventional in-wheel drive unit suspension device in which left and right in-wheel drive units are coupled to the vehicle body by left and right arms, respectively, that extend in the lengthwise direction of the vehicle, and the left and right arms are coupled together via a beam that extends in the vehicle widthwise direction.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved in-wheel drive unit suspension device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.